Dual anti-pseudomonal and resistance-modulatory actions of Sida acuta (Malvaceae) via BamB–OprM targeting: insights from integrated metabolomics, computational, and in vitro analyses
Armel Jackson Seukep, Helene Gueaba Mbuntcha, Cromwel Tepap Zemnou, Arnaud Fondjo Kouam, Victor Kuete, Mingquan Guo · Pharmaceutical Biology · 2026
Context The growing multidrug resistance (MDR) of Pseudomonas aeruginosa presents a pressing global health challenge and demands novel solutions. Medicinal plants offer a largely untapped reservoir of structurally diverse compounds with promising antibacterial and adjuvant potential.Objective This study investigated Sida acuta Burm.f. (Malvaceae) as a reservoir of dual-target phytochemicals capable of modulating resistance.Materials and methods An integrated workflow combining LC/Q-TOF-MS metabolomic profiling, molecular docking (MD), dynamics simulations (MDS), and microbiological assays was applied to the ethyl acetate fraction of the aerial parts (SAAP–EA).Results Metabolomic analysis identified 35 compounds, including biochanin A (BCA), resveratrol (RSV), methyl gallate (MG), 3-hydroxycinnamic acid (3-HCA), and azelaic acid (AZA), with favorable drug-likeness. Their toxicity predictions indicated low risks of acute toxicity (LD50 >900 mg/kg), mutagenicity, and carcinogenicity, but flagged a potential nephrotoxicity risk requiring further investigation. MD and MDS revealed stable RSV and BCA binding to both BamB (outer membrane biogenesis) and OprM (efflux), while 3-HCA and AZA preferentially targeted OprM with higher affinities than reference inhibitors. Hydrogen-bonding supported specificity and complex stability. Experimentally, SAAP–EA showed potent bactericidal activity against clinical MDR P. aeruginosa (MIC 32–256 µg/mL) and synergized with β-lactams, fluoroquinolones, and tetracyclines, achieving up to 64-fold MIC reductions at sub-inhibitory doses. The dual inhibition of membrane assembly and efflux likely underlies the observed resistance-breaking effects, facilitating intracellular antibiotic accumulation.Discussion and conclusions These findings establish a mechanistic basis for translating ethnopharmacology into therapeutic strategies against MDR Gram-negative pathogens. Future work should prioritize in vivo validation and preclinical optimization of lead dual-target adjuvants.